Core Summary: The Clinical Core seeks to improve the diagnosis and management of individuals with Parkinson disease (PD) through its support of the JHU Udall Center and Clinical Project 3. With this funding period request, the Clinical Core will add biofluid ascertainment (blood, urine, and cerebrospinal fluid (CSF)) to its existing 15-year longitudinal study and brain autopsy program. Through the collection of biofluids from individuals who undergo autopsy the Clinical Core is uniquely situated to allow the Clinical Project to identify PD biomarkers. In addition, to ensure that the Clinical Project has sufficient CSF to complete its aims, the Clinical Core will be responsible for obtaining CSF through collaborations with other cohorts both within and outside JHU. The Clinical Core also seeks to fulfill the mission of the JHU Udall Center through its efforts to educate patients, their families, and health care providers regarding the Center's research activities, PD diagnosis and treatment.